IBM's Power6 push began this week with a tweak to AIX support. In a letter to customers, IBM vowed to support future updates to AIX 5.3 for an additional two years. This appears to be IBM's Power6 concession, since the vendor, according to our sources, will announce Power6 systems this month and ship them in the middle of the year but won't have AIX 5.4 available for months. Normally, IBM would like to have a new major release of AIX ready for its new processors and have customers upgrade accordingly. No such luck.